The present invention relates to a flanged prosthesis of the type comprising a tubular body equipped at one end with an external flange designed for the anastomosis of the prosthesis to a tubular duct equipped with an opening.
It also relates to a method for manufacturing such a flanged prosthesis.
Flanged prostheses of this type are used as vascular prostheses, in vascular surgery, to treat unhealthy blood vessels, particularly portions of arteries, by shunting or by substitution.
As illustrated in document FR-A-2,751,867 describing a prosthesis such as this, these prostheses are connected to a tubular organic duct such as a vein or an artery, facing an opening formed in this duct.
The flange, which is at the end of the tubular body, allows the prosthesis to be attached using plastically or elastically deformable clips or staples.
The flanged prosthesis described in document FR-A-2,751,867 is made either by thermoforming its end portion or alternatively by bonding or welding a separate attached flange to the end of the tubular body.
That document tackles only the technologies that can be employed, without giving a precise description of the actual methods of manufacturing this flanged prosthesis.
Thus it is very awkward, using these technologies, to produce in a simple way a flanged prosthesis whose structure is satisfactory and which can be implanted reliably in the human body.
The object of the invention is to provide a flanged prosthesis which can be manufactured on an industrial scale and which has satisfactory reliability for durable implantation in the human body, and a method for manufacturing it.
To this end, the subject of the invention is a flanged prosthesis of the aforementioned type, characterized in that the flange is formed of a textile material and comprises at least one seam which shapes it at the end of the tubular body.
According to particular embodiments, the prosthesis comprises one or more of the following features:
the flange comprises a first ring secured, around its interior contour (surface), to the end of the tubular body, and a second ring surrounding the tubular body and running roughly against the first ring, these rings being joined together around their exterior contours (surfaces);
the first ring is connected to the tubular body by an interior first peripheral seam, and the first and second rings are joined together by an exterior peripheral seam;
the first and second rings are formed integrally with the tubular body, a peripheral fold line being formed between the first and second rings, and the second ring comprises at least one transverse seam;
the first ring comprises at least one transverse seam;
at least one of the seams runs roughly radially;
the second ring comprises two seams running radially on each side of the tubular body, roughly along one and the same diameter of the second ring; and
the first ring comprises a radial single seam running roughly at right angles to the diameter along which the radial seams formed on the second ring run.
A further subject of the invention is a method for manufacturing a flanged prosthesis of the type comprising a tubular body equipped at one end with an external flange designed for the anastomosis of the prosthesis to a tubular duct equipped with an opening, characterized in that it comprises the following steps:
manufacturing a tubular portion intended to form the tubular body;
manufacturing first and second roughly flat annular elements from a textile material, the first and second elements having roughly identical exterior contours;
sewing the first annular element to one end of the tubular portion using a peripheral seam formed along the interior contour of the first annular element; and
sewing the first and second annular elements together along a peripheral seam formed along their exterior contours.
As an alternative, the method comprises the following steps:
manufacturing a precursor prosthesis from textile material, comprising a tubular skirt, from one end of which at least one tubular arm intended to form the tubular body of the prosthesis emerges, the diameter of the tubular skirt being greater than the diameter of the arm,
folding the tubular skirt back on itself around the tubular arm to form a first ring extending the tubular body and a second ring extending the first ring and running around the tubular body, and
making at least one seam in the second ring so as to reduce its internal circumference and thus form the flange which consists of the first and second rings.
Advantageously, the step of folding the tubular skirt back on itself is performed around a rigid form comprising at least one disc-shaped part around which the flange is made.